A web site customer who abandons their shopping trolley in mid-purchase is unlikely to return, so getting the ordering and payment process spot on is crucial.
There are numerous reasons behind a potential purchase being aborted before the checkout. Some such as delivery charges and comparison shopping etc. may be outwith your direct control, but there are plenty other factors over which web site owners can exert their influence. It’s essential that those aspects of the shopping experience over which we have control are properly addressed to ensure the highest possible customer conversion rates.
Fears about security are a number one concern for any web site so present prominently information about server security and display security and verification logos as appropriate. Customers want reassurance before they will part with credit card details, therefore provide links to information about your security measures, ensure https appears in the browser bar and flag up to users whenever they enter a secure page.
While security can be considered a no-brainer to ensure sales, just as important is the ordering and payment process. Ensure it is smooth and efficient with as few pages and steps to negotiate as possible and practical to elicit the necessary data for the transaction. A big help in this regard is indicating where users are in the process and how many more steps to go until their order is placed.
Weed out, too, unnecessary distractions and fine-tune all the steps so that questions appear in a logical sequence, avoid duplication and are as unambiguous as possible. Think of the order and payment journey being made by the customer and offer details of shipping delivery times, costs and provide opportunities to access FAQs, contact details, and terms and conditions, but without taking the user out of the transaction process.
As a final usability pointer, resist the temptation to harvest marketing data from customers as they are likely to resent inputting data not directly relevant to their purchase.